I've never played the PCE version of 4 (just the SNES/SFC one), so I'm going to go with 3. (I've never played the PCE one of that one either, but I've heard the Genesis/MD one is extremely close.)
I've played the PCE versions of 1 and 2 (on my PS3), and while I agree that 1 is much nicer technically than the others, and the plot is pretty amazing... 3 just stands out more to me for some reason.
I'm also not sure why, but the MSX2 version of Valis II was a lot of fun for me. It's technically way inferior to the PCE one, but when I was growing up, I'd played SD Valis and compared to that, anything was a HUGE step up, so when I got my hands on the MSX2 version, I was like "whoa."
MSX version of Valis 1 kind of sucked though.
I've played the PCE versions of 1 and 2 (on my PS3), and while I agree that 1 is much nicer technically than the others, and the plot is pretty amazing... 3 just stands out more to me for some reason.
I'm also not sure why, but the MSX2 version of Valis II was a lot of fun for me. It's technically way inferior to the PCE one, but when I was growing up, I'd played SD Valis and compared to that, anything was a HUGE step up, so when I got my hands on the MSX2 version, I was like "whoa."
MSX version of Valis 1 kind of sucked though.